Detonating material

The fire department blamed the accident on welders cutting in hazardous areas without a fire watch, highly combustible structural components (fiber-glass-resin), high-density storage of highly flammable and detonable material, spilled ammonium perchlorate about the plant, and high w ind conditions. 

Liquid mixtures with detonable materials (picric acid, nitromethane) were extremely powerful explosives, and those with nitrobenzene or dimethylformamide less so. 

The effect of a detonation depends on the shock wave, that is, an immediate peak overpressure followed by a longer period with an underpressure. The strength of the shock wave depends on the mass of the detonating materials. Detonations are mostly induced by initiation sources. In some cases, a deflagration may make a transition into a detonation. Working with chemicals and systems under plant conditions where a detonation can be induced is NOT recommended. Whether or not a chemical or chemical system can detonate can be determined only by specific tests as outlined in Chapter 2. 

In general, detonation test apparatus consists of a steel tube that is filled with the substance under investigation. One end of the tube is provided with a booster charge consisting of an electric detonator covered by detonative material. The other end is either closed or provided with a witness plate. One type of steel tube apparatus is provided with a velocity probe to record the shock wave velocity as shown in Figure 2.28. 

The aim of this study is to show that the law of density variation in detonating material may accelerate the propagation of the deton wave, raise the temp pressure behind the wave front, and greatly influence die motion of the deton gases. Similar effects are bound to occur in tubes of variable cross-section with a const density of detonating material... 

Unlike commercial blasting caps, homemade caps can be made as needed and then be boosted by inclusion of extra detonating material. These more powerful caps work well with sleepy homemade or mili tary-grade explosives, both of which can be quite difficult to detonate. 

The variable initiator test using the MKIII ballistic mortar and the ballistic pendulum is very effective to evaluate these materials 35 c 8 . The probability of occurance of deflagration can be determined from the strength of explosion in the ballistic mortar or ballistic pendulum test. However, this method cannot be used for detonating materials that may damage the test equipment... 

The product of this 8 year systematic study was the publication of the safety design manual entitled, "Structvires to Resist the Effects of Accidental Explosions" (Army s Publication TM5-1300). An outline of studies leading to publication of this manual is shown in Fig 1. The manual contains procedures, charts, and tables required to establish the environment of an explosion and its output in terms of blast and fragments. The relations are presented in such a manner that the type of protective structure may be selected, analyzed, and designed to provide a safe level of protection for personnel, equipment, and for separation of potentially mass detonating materials. 

Bellncci, J.J., Simonetti, A., Wallace, C. et aL (2013). Isotopic fingerprinting of the world s first nnclear device nsing post-detonation materials, Anal. Chem. 85, 4195 198. 

From the point-of-view of technological practice it is important to study the effects of inert admixtiues added to EMs upon the sensitivity of resulting mixtures (see also Sect. 3.1, papers [92,93]). Desensitization of detonable materials by diluent was studied by Rice et al. [ 113] on the basis of molecular-dynamics investigation. An inert diluent, a heavy material, was inserted into a crystalline explosive in two ways. The first series of simulations investigates the attenuation of the energy of a detonation wave in a pure explosive after it encounters a small layer of crystalline diluent that has been inserted into the lattice of the pure explosive. After the shock wave has passed through the diluent layer, it re-enters the pure explosive. Unsupported detonation is not re-established unless the energy of the detonation wave exceeds a threshold... 

II-2. Explosion as defined here consists of detonation and deflagration. The difference between a detonation and a deflagration is primarily the bum rate of the explosive material in question. In general, solid detonating materials have bum rates in excess of 4000 m/s. The characteristics of several detonating types of solid explosives are given in Table II-I. 

The well-known explosive tetraazidoqninone has also been reinvestigated and the crystal structure in a charge transfer addnct with tetrathiafnlvalene determined (Figure 13.5). The potential use of the adduct as a light detonant material under laser irradiation was examined. 

The booster is used either as an intermediate stage to detonate material that is too insensitive to be detonated by the relatively weak initiator or to ensure complete detonation of the main charge. The main or bursting... 

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